This invention relates to an improved pocket design for removable segments used in roll-type briquetting presses.
A conventional roll-type briquetting press includes a pair of power-driven rolls which are journaled on parallel axes, and whose circumferential faces contain a series of mating cavities. These mating cavities are contained in the removable segments that form the circumferential face of the briquetting roll. The rolls are usually held together by hydraulic pressure devices, whereby as they rotate, loose material fed between them is compacted within the cavities. For example, partially reduced particulate iron are may be briquetted at temperatures as high as 1350.degree.F and under loads as great as 100,000 pounds per inch of effective roll width.
Difficulties have been encountered, however, in that the particulate reduced ore tends to flow at a significantly greater rate at the center of the face of the roll than it does at the outside of the face, i.e., near the stationary check plate usually employed to retain the ore in the area between rolls. One of the undesirable results of the uneven flow is an uneven distribution of density in the briquettes, which leads to a higher rate of physical degradation and a greater tendency to reoxidize.
The object of the present invention is to create an improved design for the cavities in the briquette-roll segments, which will provide a better flow of particulates from the center of the roll face to the outside, and thus produce a briquette with more uniform density.
Prior to the present invention, it has been known to employ briquetting rolls with angular cavities. See, for example, Decker et al. U.S. Pat. No. 2,958,902. The configuration shown in Decker, however, which places the mold segment at an angle carried across the entire face of the roll, is not able to create a flow of material towards both sides of the mold face as ours is.